Suspension and load equalizing system for vehicles



D. H. SPANGLER- 8 Sheets-Sheet 1 Filed Ders.l 10, 1945 July 9, 1946.

SUSPENSIONAND LOAD EQALIZING SYSTEM FOR VEHICLES Jul'y 9,'1'946.

D. H. PANGLER SUSPENSION AND LOAD EQUALJZING SYSTEM FOR VEHICLES Filed Dec.

10, 1945 8 Sheets-Sheet 2 enfer @if Afp/m31@ N ,QJMMQMM Ban '3% July 9, 1946. D. H. -sF'ANcsLERl 2,403,833

v SUSPENSION AND LOAD EQUALIZING SYSTEM FOR VEHICLES 4 Filed Dec. 10, 1945 8 Sheets-Sheet 5 ,CLAQM; .l www...

July 9, 1946 I D. H. SPANGLER. 2,403,833

SUSPENSION AND LOAD EQUALIZING SYSTEM FOR VEHICLES 8"-'Sheets-Sheet 4 Filed Dec. 10, 1945 ,Daniel *Span-tyler; .WCMQM'-S1ZSLMLM I I www.

July 9, 194.6. D. H. SFANGLER` SUSPENSION AND LOAD EQUALIZING SYSTEM FOR VEHICLES` Filed Dec. 10, 1945 8 Sheets-Sheet 5 D. H. sPANGLER 2,403,833

Filed Deo. 16, 1945 8 sheets-sheet s P11291, LMZMM -y /l /c N l/ K l/ zeZ-J'f aan SUSPENSION AND LOAD EQUALIZING` SYSTEM FOR VEHICLES QN bwl t l@ July 9,1946. I

July 9, 1946. D. H. sPANGLER SUSPENSION AND LOAD EQUALIZING SYSTEM FOR VEHICLES Filed Dec. l0, 1945 8 Sheets-Shee'fI '7 July 9, 194e;

SUSPENSION AND` LOD EQUALIZING SYSTEM FOR VEHICLES Filed Dec. 1o, 1945 8 sheets-sheet s Ifjg.1?l

I ""Tn" D. H. SPANGLER n 2,403,833 1 Patented July 9, 1946 AUNITED SUSPENSION AND LOAD .EQUALTzING SYSTEM FOR VEHICLES Daniel Herbert Spangler,` Hamburg, Pa.

Application December 10, 1945, Serial No. 633,966

The present invention relates to suspension and load equalizing systems for vehicles.

An important Object of the invention is to pro vide suspension systems for vehicles which will resiliently support one or more axles to withstand the stresses resulting from road shock.

Another object of the invention is to provide suspension systems for use with dual axle assemblies Which will permit the -axles to mOVe Vertically with respect to each other andthe vehicle frame, but which will withstand all torsional stresses.

Another object of theinvention is to provide a suspension system whereby one or more axles will be permitted to move vertically with respect to the vehicle frame, but the axle or aXles will be kept in properly tracking relation' with regard to the vehicle.

A further object ofthe invention is'to provide a resilient suspension element for vehiclesv and which is of such design that it will automatically adjust itself to accommodate varying loads andy road shocks. A still further object is to provide a suspension structure which will eliminate side sway of the A vehicle. Y

In 4anyV vehicle using leaf spring suspension, all unevenness of the road sets up a twisting action. This twist is transmitted directly yto the vehicle frame through the leaf spring pack since the very structure of a series f spring leaves does not allow for any torsional strain absorption.

With my coil spring suspension, the spring transmits only vertical motion and all torsional stress is dissipated through the various compensating joints and torque rods included in the structure.

Other objects and advantages of the invention will be apparent from the following description and drawings, wherein like numerals refer to Similar parts throughout the several views.

In the drawings: Y Figure 1 is a side elevation of ai'orm of dual axle suspension included in the present invention,

the View'showing the axles and axle housings in 14 Claims. r(Cl. ZBO-104.5)

yline -5 of Figure 1 2 Figure 4 is a transverse vertical section von the line 4.--4 of Figure '1.

Figure 5 isa vertical transverse section on the Figure 6 is a vertical transverse section on the line 6-6 of Figure 1.

Figure 7 is a top plan View of the beam illustrated in Figure 1.

Figure 8 is a side view of the beam oi Figure 7, with a portion in vertical longitudinal section.

Figure 9 is an end View of the beam of Figure '7.

Figure 10 is a vertical transverse section on the line Ill-lil of Figure 8.

Figure 11 is a vertical transverse section on the line lI-II of Figure 8.

Figure 12 is a detail view Showing the resilient mounting included in the present invention in sidek elevation.

Figure 13 is a vertical section on the line I3I3 of Figure 12.

Figure 14 is a horizontal section on the line lli-I4 of Figure 13. Y

Figure 15 is a side elevation of la modied form of suspension for dual axle assemblies, the view showing the axles and axle housings in vertical section andbeing taken on .the line l5|5 of Figure 16. v

Figure 16 is a plan view of the Figure 15 structure.

t3o Flgurel'l `is an end view -Of theFigure l5 structure.

Figure 18 is a transverse vertical section on the line |8--I8 of Figure 15.

Figure 19 is a transverse vertical section on th line |9-l9 of Figure 15, and l Figure 20 is a transverse section on the line '2D- 20 of Figure 15.

Referring to Figures 1 to 14, inclusive, the principal elements illustrated in those figures are as follows: The numeral designates each of the two side frames of a vehicle, for example, a motor truck or atrailer, andthe numeral 32 designates a usual cross-brace for the vehicle. As best shown in Figures 2 and 3, an inverted U- beam 33 is secured to andextends between the two side frame members 3l) at a point between the axle housings 34 and 35 of a dual or tandem axle assembly. vA resilient or shock absorber element 36 comprising two vertically opposed cylinders is secured to each side frame 30 within cross-beam 33. The lower cylinder of each element -rigidly carries a bracket 31 on which a beam 38 is pivotally mounted for swinging movement about va, horizontal axis. Below the pivot for beam 38, each bracket 3'! also includes axial- 1y spaced pivots for a pair of torque rods 38 and opposite directions longitudinally of the beam The ends of the beam 38 are respectively connected by means of universal or gimbal connections 4I to anged collars xed to the axle housings 34 and 35, the connection 4| being positioned above the axle housings. The free ends of the torque rods 3.9 yand 40 are connected to the flanged collars of the axle housings by a universal joint 42 such as a ball and socket connection, this connection being, positioned below the axle housings. A radius rod 43 is pivotally connected to each end of each beam 38 so that the beam and radius rod may swing relative to each other about an axis extending transversely of the vehicle. Each radius rod 43 isconnected to a bracket 44 which projects downwardly from the vehicle side frame at apoint spaced from the axle housings and on the opposite side of the axle housings from the resilient element 35. Each radius rod 43 is connected to its corresponding bracket 44 by a connection generally designated 45 and which is of such design that the radius rod may swing withrespect to its bracket 44 on an axis transverse ofthe vehicle and may also slide lengthwise of the vehicle frame and bracket 44.

The structure of Figures 1 to 14 may be described in more detail as follows: The resilient or shock absorber element 36 provided on each side frame 38 of the vehicle includes an outer and upper cylinder 48 closed at its upper end and this cylinder is welded or otherwise secured in the underside of the cross-beam 33 as best shown in Figures 12- and 1.3. Asis indicated in the latter figure, each end of the cross-beam extends into the adjacent side frame 36 and the side frame lower ilange is recessed so that the cylinder 48 may extend downwardly in the frame. In this way, each cylinder 43 is rrnly Secured aginst sidewise movement in any direction. shown in Figures l, 12 and 13, a lower and movable cylinder 49 is reciprocably mounted in each xed cylinder 48, the lower -end of each cylinder 49 being secured to the upper face of the bracket .31 so that the bracket closes the lower end of this cylinder. A block i) of wood or the like may .be mounted within cylinder 4S to rest on bracket 31. A helical spring 5i extends between the up- 4helical spring 53 is provided. However, as shown in Figure 13, spring 53 is of shorter length than the spring 5I and will not normally contact with 4the upper` end wall 52 of the fixed cylinder 48.

Under heavy load conditions, or under ext-reme road shock, the outer and lighter spring 5I will be compressed sufficiently to cause a part of the load to be absorbed by the inner and heavier spring 53.' The lprovision .of a lighter normal load carrying and shock absorbing spring to support weight and take up shock makes the present Asuspension more flexible under such conditions. Nevertheless, the provision of theV inner "and heavier spring enables the structure to prop- `erly absorb heavierroad shocks. In order to eX- clude` dust and dirt from the interior of the cylinder structure, suitable dust covers-49 may be provided, also packing rings may be installed to As best i 4 retain lubricating materials within the cylinder structure, all as illustrated'in Figure 13.

It will be observed that the cylinders 48 and 49 fit closely, are of such large diameter and have sufficient overlapping length under all conditions that side sway of one with respect to the other will be prevented. Therefore, the body of the vehicle cannot have the objectionable side sway which occurs with lear springs.

The construction of the bracket 31 is best illustrated in Figures 12 and 13. Referring to these figures, it will be observed that the upper portion 55 of the bracket has the form of an upwardly flanged circular disk, which, as stated above, forms the bottom of the lower and movable cylinder 43. An aperture 56 extends horizontally through the bracket 31 adjacent its upper portion 55 and a pin 51 extends through and is rotatable in this aperture to serve as a :pivot for the beam 38 as Vhereinafter described. The extreme lower portion of bracket 31 is bifurcated and a pin 58 extends through and is xed in apertures in this portion to serve as a connection for the torque rods 39 and 40 as hereinafter described.

The beams 38 provided adjacent each side frame 38 of the vehicle are pivoted to the respective brackets 31 as best illustrated in Figure l. The detailed structure of each beam 38 is shown in Figures 7 and 8. It will be observed from these views that each beam is of generally U-shaped form in transverse section to include a top wall 60 and side walls El, with transverse webs 62 adjacent its ends, additional webs 63 being provided adjacent the median portion of the beam. `At the central portion of the beam the top wall G8 iscut away so that the beam may laterally enclose the bracket 31 as illustrated in Figure 13. At its upper and Ycentral portion, each side wall 6l of the beam is provided with an aperture 64 in which the ends of the pin 56 of bracket 31will be fixed.` It will be observed from Figure 1 that each beam 38may swing with respect to its bracket 31 about an axis extending transversely of the'vehicle, each lbeam also having a vertical movement with its bracket 31 and the lower cylinder 49 of the corresponding resilient'supporting element 3S.

The torque rods 39 and 40 are ofV solid construction and, as best illustrated by the dotted line showing of those rods in Figure 2, and the sectional showingthereof in Figure 4, each rod is attened along vertical lines at its inner end and the flattened portion includes an aperture which surrounds the pin 58 carried in the lower end of each bracket 31. As shown in Figures 4 and 13, the pins 58 may be flanged intermediate their length to space the torque rods from each other. By this arrangement, the torque rods may swing in vertical planes with respect to the brackets 31 and the torque rods will also move vertically with the bracket. It will be observed that on the bracket 31 the points of pivotal connection of the torque rods and beam 38 are xed with respect to each other and are vertically spaced along the median lines of the brackets.

The structure whereby the opposite ends of each beam 38 are connected to an axle housing is as follows: As is illustrated in Figures 1 to 11, an extension 10 projects beyond the web 62 of each end portion of a beam, the extension 10 including a downwardly extending shoulder 1I at its outer end. Aligned apertures 12 and 13 are provided in each shoulder 1I and web 62relying in the same plane.

spectively., By this construction, a downwardly facingV recess 14 is provided at each end of each beam 38. As is best shown in Figures 3 and .5, a collar or sleeve 15 is fixed to each end Yof each axle housing at a point inwardly of the adjacent wheel and beneath the end of the corresponding beam 38. A sleeve 15 appears in side elevation in Figure 1 and it will be observed from that gure and Figure 5` that each sleeve includes a central portion 16 which embraces the axle housing, a downwardly projecting tongue 18 at its outer edge and two upwardly projecting tongues 11, the tongues 11 being spaced the length ofthe collar 15. A pin 18 is iixed in apertures in the upwardly extending tongues 11 and this pin carries a cruciform element 19 shown in the broken away portion at the lower left hand portion of Figure 2. The cruciform element 19 is rotatable about the xed pin 18 on an axis transversely of the vehicle. Pins 80 are xed in cruciform element 19 to project at .right angles to pin 18, the axes of all of these pins The pins 88 are rotatable on an axis lengthwise of the vehicle in the apertures 12 and 13, respectively, of the end recess 14 of beam 38. Therefore, cruciform element 19 is rotatable on an axis extending length- Wise of the vehicle. v

It will be observedthat the pivot points 4l and 42 lie in the same vertical plane as the axis of the corresponding axle housing and axle.

ByA this construction, the beam k88 and an axle housing may swing with respect to each other on an axis extending transversely of the vehicle and, in addition, have relative movement `on'an axis extendinglongitudinally of the vehicle. Therelfore, yan axle housing Ymay either move upwardly or-"downwardly without endwise tilting, or may tilt Vfrom end to end, because ofthe universal joints 4| thus provided between each end of each axle housing andthe corresponding ends of the beams'38. n j kAs indicated in Figures 1 and 5, the outer end of each-torque rod 391and 40 is connected to the lower-tongue 16 of axle housing collar 15 by a balland socket joint, thetongue 15 carrying a-stud 8| including a ball-shaped portion to i'lt a socket in the free end of the corresponding torque rod. This `universal connection, generally designated bythe numeral 42, will further enable the axle housing to tilt lengthwise or move vertically and translationally as described in the Ypreceding' paragraph.

'It will be perceived that the provision of the beam 38 and the torque rods 39- and 48, at each wheel end of the tandem axle assembly, with the beam and torque rods pivoted to a bracket between the two axle housings, provides a parallelogram connection between both ends of the axles. More particularly, neither axle housing can rotate on its own axis and with respect to the other axle housing, regardless of whether it moves up and down by endwise tilting or translationally, because the pivot points 4| and 42 are the corners of one end of a parallelogram which has 'its opposite end corners positioned at the pivot points 4I rand 42 at the same end of the other axle. In short,'though an axle housing may move upwardly or downwardly with respect to its opposite end, as wellas with respect to the other jaxle housing, a Vpivot point 4l will always be `directly above a pivot point 42V andthe axle housings cannot turn with respect to each other. "f Each radius rod 43 is provided with an aper- 'ture 85 in its inner end as best-shoWn-in Figures `outer portion of each radius rod 431s slidable in and extends through a cruciform element 88, Each element 88 includes pins 89 fixed thereto (Figure 6) and rotatable in apertures in the lower ends of the bracket 44. In this way, the radius rod can swing both with respect to beam 38 and bracket 44 on axes extending transversely of the vehicle. 'A spring 99 encircles each radius rod 43 beyond the cruciform tting 88, the inner end of the spring bearing on fitting 88 and the outer end of the spring bearing against a washer vand nut assembly l9| positioned at the outer end of the radius rod. While each radius rod may slide through its fitting 88 and thereby generally lengthwise of the vehicle, the spring 90 exerts an outward pull on the rod.

The radius rods 43 assist in preventing the dual axle assembly from rotating about a vertical axis midway between the spring mounts 36,

through the fact that a shock absorber element 35a is positioned at each end of the dual axle assembly primarily prevents such rotation and thereby assures proper tracking. The radius rods 48-and their associated springs 58 have the further function o urging the axlesl to return smoothly to anormal position from any upward or downward movement with respect to the vertical frame. That is, the fact that the radius rods are provided at both ends of each side of the assembly holds the assembly under tension and prevents undue horizontal and vertical swing of the beams 38 relative to the brackets 31. Also, the spring-loaded radius rods act as dampeners or shock absorbers with regard to vertical movement of the springs 5l and 53.` l It will be observed from the lower left hand portion of Figure 2, and also from Figure V5, that the cruciform elements 18 have a width less than the space between the tongues 11l on the correspending collars 15. As is also indicated in these figures, when the dual axles are horizontal, each cruciform element 18 will be so positioned on` its cross-pin 18 that av space will exist being the outer tongue 11 and the'adjacent end of theelement 19. Also, as shown in Figure 4, and Vin dotted lines in Figure 2, the inner ends ofthe torque rods 39 and 48 are normally spaced'from the pin flange 58 and the inner arm 31 `of the ture described in yFigures 1 to 14 will hold the axles of the dual axle assembly against rotation with respect to each other, but without preventing either end of either axle from moving vertically infaccordance with the road surface.' Moreover, the resilient mounting 36 fo-r each beam 38, taken with the springs 90 of the radius rods, will insure that all road shocks will be smoothly absorbed. It will be understood that the structure described in Figures 1 to 14 may be used -in an assembly where both axles are either dead or driven, or one axle isdead and the other driven.

Referring to Figures 15 to 20, which illustrate a modified form of dual axle assembly, this form differs from that of Figures 1 to 14 primarily in that the torque rods used therein are positioned above the beams and radius rods are connected directly to the axle housings, instead of to the beams.

In more detail, in Figures 15 to 20, the numeral designates the side frame elements of the vehicle, these elements being rigidly cross-connected by a transverse beam I0 A resilient supporting element or shock absorber 36a, is positioned at the intersection of each side frame |00 and cross-member |0| just as has been described above in connection with the structure of Figures 1 to 14. The element 36a has a construction identical with that described with regard to the preceding figures.

As is best shown in Figure 18, a bracket |02 provided at the lower end of the movable cylinder of each shock absorber 36a has a cross-pin |03 xed therein and provided with a central flange |03. In addition, the extreme lower portion of each bracket |02 is provided with a horizontally and transversely extending bore |04 which carries a cross-pin |05. A beam |06 is pivoted to the lower end of each bracket |02 by means of upwardly extending ears |01, the ears being apertured to engage the ends of the pin |05 and the pin being secured to the ears. Each end of each beam |06 has a pin |09 fixed therein and extending longitudinally from the beam as illustrated in Figure 15. Beyond the beam, each pin |09 has a sleeve l0 rotatable thereon, the sleeve ||0 including an upwardly extending and transversely apertured lug through which a pin ||2 extends. The pin ||2 is iixed in spaced ears ||3 which project downwardly from a fitting H0 secured near the wheel end of the adjacent axle housing ||5 and sleeve ||0 is rotatable about pin ||2. In this way, each beam |06 and the axle housings at the ends thereof may move with ree spect to each other about the axes of the pins |00 extending longitudinally of the beams and vehicle. In addition, the axle housings may swing with respect to beams on the axes of the pins ||2 extending transversely of the beams. In short, universal joints are thereby provided between the beams and axle housings.

Each axle housing fitting |4 includes an integral and upwardly extending plate |25 and a iixed pin projects laterally iro-rn each plate as shown in Figure 15, The outer end of the corresponding torque rod is p'ivoted on the pin |20, the two torque rods on each side of the assembly being respectively designated by the numerals |2i and |22. As has been indicated above, a torque rod I2! and a torque rod |22 are associated with each beam |06, the inner end of each torque rod being pivoted on the pin |03.

By the above-described pivotal connections, the axle housings can tilt with respect to the beams |06 or rotate on their axes with respect to the beam, but the two axle housings cannot turn with respect to each other because of the parallelogram relationship afforded by the beam |06 and the torque rods and the manner in which the various pivots are arranged with respect to each other.

As shown in Figure 19, the upwardly extending plate |25 of each axle housing iitting I4 also has `a pin |26 fixed therein to extend laterally. The

inner end of a radius rod |21 is pivoted on the corresponding pin |26, each radius rod extending outwardly to a bracket 44a secured to the vehicle frame at a point spaced from its axle housing and on the opposite side of the latter from the shock absorber 36a. Each radius rod |21 is slidable through a cruciform iitting 88a, which is rotatable in the bracket 44a on an axis extending transversely of the Vehicle, the crucform fitting 88a being identical with the tting 88 of Figures 1 to 14. A spring 90a is mounted about the outer portion of each rod |21 to function in the same manner as the spring 90 of the structure of Figures 1 to 14.

As is shown in Figure 18, and in dotted lines in Figure 16, the inner ends of the torque rods |21 and |22 are normally spaced from the pin iiange |03 and the inner leg |02' of bracket |02. As shown in Figure 19, the lug I carried by pin |09 is normally spaced from the outer ear l I3 of the pair of ears ||3. Because of thisarrangement,

when an axle tilts, the beam |06`and radius rods |21 will remain in their normal vertical planes.

The operation of the structure of Figures 15 to 20 is identical with that disclosed in Figures 1 to 14, the primary difference between the two structures being that the torque rods |2| and |22 of Figures 15 to 2O are positioned above the beam |06 instead of below the beams as in the structure of Figures 1 to 14. As in the previous structure, that just described can be used with either two driven or dead axles, or one of each.

'Ihe terminology used in the specification is for the purpose of description and not of limitation, the scope of the invention being defined in the claims.

I claim:

l. In a suspension and load equalizing system for vehicles, Vehicle side frame members, a tandem axle unit including axle housings, a pair of brackets, means to resiliently secure said brackets for vertical movement with relation to the respective side frame members at points between the axle housings, upper and lower elements pivoted to each of said brackets at vertically spaced points and pivotally connected to said axle housings adjacent the ends of the latter to maintain the latter against rotation with respect to each other and about their axes, and means carried by the side frames to exert tension on said axle housings longitudinally of the vehicle.

2. In a suspension and load equalizing system for vehicles, vehicle side frame members, a tandem axle unit including axle housings, a pair of brackets, means to resiliently secure said brackets for vertical movement with relation to the respective side frame members at points between the axle housings, upper and lower elements pivoted to each of said brackets at vertically spaced points and pivotally connected to said axle housings adjacent the ends of the latter to maintain the latter against rotation with respect to each other and about their axes, one of said elements being pivoted intermediate its length to said bracket and the other element comprising two rods extending in opposite directions from said bracket and longitudinally with respect to the vehicle, and means carried by the side frames to exert tension on said axle housings longitudinally of the vehicle. Y

3. In a suspension and load equalizing system for Vehicles, vehicle side frame members, a tandem axle unit including axlehousings, a pair of brackets, means to resiliently secure said brackets for vertical movement with relation to the respective side frame members at points between the l, axle housings., upper adflowergdements,pivoted to each of said bracketsat vertically spacedpoints and pivotally connected to said axle housingsadf jacent theends ofithe Ylatter to maintain-.the latter against rotationwith!A respect toA each other and about their axes.saidlower element comprising a beam pivoted intermediate its length tol said bracket and vsaid upperfelementcomprising two y rods each pivoted tosaid brackety and extending.'l in opposite directions therefrom andylongitudinally of the vehicle, and means carried by the -side frames to exert tension von said axle housings longitudinally of thefvehicle; K, n

4. In a suspensionand load equalizing system for vehicles, vehiclesideirame members, ar tanthe respective axle housings-and the free ends y ofsaid rods being pivotally connected to therespective'axle housings at a point on the latter oppositethe beamrpivot, all of said points of pivotal connection being so Vrelated that the pivot points on the corresponding: ends ofi-the vaxle yhousings define the corners of a parallelogram.

dem axle unit including -axle housings, .a pair of brackets, means to resiliently secure said brackets for vertical movement withrelation to the'respective side frame members at pointsbetween theaxle housings, upperand lower elements piv- '9. Ina suspension, and loadvequalizingasystem for vehicles, a pair of body framerside members, a 'tandem` axle -unitincluding axlev housings, -a pair of brackets, means to resiliently secure said brackets below ,and lfor vertical .movement with relation tothe. respective side frame members,- a

oted to each of said brackets at vertically spaced i points and pivotally connected to said axlehousings adjacent the ends of the latter to maintain ythe latter. against' rotation with ,respect to each other and about their axes, said upper element axle housings longitudinally of the vehicle.-

5. In a suspension and load lequalizing systemfor vehicles, a tandem axle unit including axle housings, a pair ofbrackets, means to resiliently secure said-brackets below and ,for vertical movement with relation to therespectiveside frames of the Vehicle ata point between lthe axle housings, a pair of beams, one pivoted intermediate its ends on the respective brackets and for vertical swinging movement with relation to said bracket, a pair of torque rods pivoted to each of rsaid brackets at a point vertically spaced with respect to the corresponding beam pivot point, said torque rods being pivoted for movement in a substantially vertical plane, said beam and the free v comprising a beam pivotedintermediate its A -length, to saidbracket and said lower element comprising, twd'rods each rp-ivoted'to saidbracket .and extending-in opposite directions therefrom and longitudinally of the vehicle, vand meansv car-I ried by the side frames to exert tensionen said pair of beams, each pivoted intermediate its ends to one of said bracketsv and, adapted ,to lextend longitudinallyof the vehicle-frame, af pair of torque rods pivoted to each ofl said brackets be'- low said beams, the respective rods oVf-eachpair projecting in opposite directionsand longitudinally of'said beams, the-ends of said beams .being pivotally connected tothefuppenportions' of .the ends of the respective yaxleh'o'using andgthe .free endsof said rods being pivotally connected to the lower portions of the ends ofthe respective axle housings,` all of said poi'ntsgof pivotal `con.- nectionbeing so related that lthepivot.points ,on the corresponding ends or the axlefhous'ings d efine the corners ofa parallelogra'm.,v l, 10. In a suspension andv load equalizing system for vehicles, a pair ,of bodyirameside members, a tandem axle, unit 'including'axle housings, a pair of brackets, meansltolresiliently .secure said brackets below andjfor vertical movement with relation to the'respectivefside'frame members, a pair of beams, each pivoted: intermediateV its ends to one of said brackets and adapted to extend longitudinally ci" the vehicle frame, a pair A of torque rodsV pivoted to each of said brackets ends of said torque rods being pivoted to the respective axle housings at points on said housings vertically opposite each other, said last-named pivot connections Vbeing universal joints, andy means to resiliently connect corners of said beam, torque rod and axle housing assembly :to respective points on the side frames of the vehicle which are spaced lengthwise of the Vehicle fromsaid assembly.

6. A suspension and load equalizing system of the character described in claim 5 wherein the beams are pivoted to the brackets and axle housings above the corresponding pivot points for the torque rods.

7. A suspension and load equalizing system of the character described in claim 5 wherein the beams are pivoted to the brackets and axle housings below the corresponding pivot points for the torque rods.

8. In a suspension and load equalizing system for vehicles, a pair of body frame side members, a tandem axle unit including axle housings, a pair of brackets, means to resiliently secure said brackets below and for vertical movement With relation to the respective side frame members, a pair of beams, each pivoted intermediate its ends to one of said brackets and adapted to extend longitudinally of the vehicle frame, a pair of torque rods pivoted to each of said brackets at a above said beams, the respective rods of each pair projecting in opposite directions and longitudinally of said beams, the ends of said beams being pivotally connected to the lower portions of the ends' of the respective axle housings and the free ends ofr said rods being pivotally connected to the upper portions of the ends of the respective axle housings, all of said points of pivotal connection being so related that the pivot points on the corresponding ends of the axle housings dene the corners of a parallelogram.

11. In a suspension and load equalizng system for vehicles, a pair of body frame side members, a tandem axle unit including axle housings, a pair of brackets, means to resiliently secure said brackets below and for vertical movement with relation to the respective side frame members, a pair of beams, each pivoted intermediate its ends to one of said brackets and adapted to extend longitudinally of the Vehicle frame, a pair 'of torque rods pivoted to each of said brackets at a point vertically spaced'with regard to the pivot of the corresponding beam, the respective rods of each pair projecting in opposite directions and longitudinally of said beams, the ends of said beams being pivotally connected to the ends of. the respective axle housings, the free ends of said rods being pivotally connected to the respective axle housings at a point on the latter vertically opposite the beam pivot, al1 of said vaxle housings denne the corners of a parallelo- Igram, radius rods, one pivoted to and extendling longitudinally from each corner of the axle 'jacent axle housing from said rst-named bracket, each of said radius rods being longitudinally slidable and vertically tiltable with respect to its vehicle frame bracket. i

12. In a suspension and load equalizing system for vehicles, a pair of body frame side members, a tandem axle unit including axle housings, a pair of brackets, means to resiliently secure said brackets below and for vertical movement with relation to the respective side frame members, a pair of beams, each pivoted intermediate its ends to one of said brackets and adapted to extend longitudinally of the vehicle frame, a pair of torque rods pivoted to each of said brackets below said beams, the respective rods of each pair projecting in opposite directions and longitudinally of said beams, the ends of said beams being pivotally connected to the upper portions of the ends of the respective axle housings and the free ends of said rods being pivotally connected to the lower portions of the ends of the respective axle housings, all of said points of pivotal connection being so related that the pivot points on the corresponding ends of the axle housings dene the corners of a parallelogram, kradius rods, one pivoted to and extending longitudinally from each corner of the respective beams, brackets adapted to receive the free ends of the respective radius rods and secured t'o the corresponding vehicle side frame at a point onthe opposite side of the adjacent axle housing from said first-named bracket, each of said radius rods beyhousing and beam structure, brackets adapted to y [ing longitudinally sudabie and vertically unable with respect to its vehicle frame bracket.

13. In a suspension and load qualizing system for vehicles, a pair of body frame side members', a tandem axle unit including axle housings,

'a pair of brackets, means to resilientlyvsecure said brackets below and for vertical movement with relation to the respective'side frame members, a pair of beams, each pivoted intermediate "its ends to one of said brackets and adapted to extend longitudinally of the vehicle frame, a pair of torque rods pivoted to'each of said brackets above said beams, therespective rods of each pair projecting in opposite directions and longitudinally of said beams, -the ends of said beams being pivotally connected to the lower portions of the ends vof the respective axle housings and the free ends of said rods being pivotally connected to Vthe upper portions of the ends of the respective 'axle housings, all of said points of pivotal connection being so related that the pivot points on the corresponding ends of the axle housings dene the corners ofra parallelogram, radius rods, one pivoted to and extending longitudinally from each end of each axle housing,'brackets adapted to receive Ythe free ends of the respective rods and secured to the corresponding vehicle side frame at a point on the opposite side of the adjacent axle housing from said first-named bracket, each of said radius rods being longitudinally slidable and vertically tiltable with respect to its vehicle frame bracket.

1 4. A suspension and load equalizing system of the character described in claim 1 wherein the connection between'one of said elements and the vaxle housings comprises a universal joint includling a cruciform member.

DANIEL HERBERT SPANGLER. 

